Description: The naive version of the class of reflexive relations { r e. Rels | A. x e. dom r x r x } is redundant with respect to the class of reflexive relations (see dfrefrels3 ) in the class of equivalence relations. (Contributed by Peter Mazsa, 26-Oct-2022)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | refrelsredund3 | |- { r e. Rels | A. x e. dom r x r x } Redund <. RefRels , EqvRels >. |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | refrelsredund2 | |- { r e. Rels | ( _I |` dom r ) C_ r } Redund <. RefRels , EqvRels >. |
|
| 2 | idrefALT | |- ( ( _I |` dom r ) C_ r <-> A. x e. dom r x r x ) |
|
| 3 | 2 | rabbii | |- { r e. Rels | ( _I |` dom r ) C_ r } = { r e. Rels | A. x e. dom r x r x } |
| 4 | 3 | redundeq1 | |- ( { r e. Rels | ( _I |` dom r ) C_ r } Redund <. RefRels , EqvRels >. <-> { r e. Rels | A. x e. dom r x r x } Redund <. RefRels , EqvRels >. ) |
| 5 | 1 4 | mpbi | |- { r e. Rels | A. x e. dom r x r x } Redund <. RefRels , EqvRels >. |